cancel
Showing results for 
Search instead for 
Did you mean: 

how can I turnoff display backlight led. GFX01M2 Board

Dev_P0
Associate

I want to program turning on/off display backlight to reduce power consumption.

 

1. how can i turn off / on display backlight led?

2. I use dt022ctft on GFX01M2. 

3. developement board is NUCLEO-G071RB

 

 

1 ACCEPTED SOLUTION

Accepted Solutions
gbm
Lead II

Check the schematic. The backlight is permanently connected to power supply via resistor R8, so there is no way to control it. You may modify the board by removing R8 from its position and soldering it in series with an NPN RET (bipolar transistor with build-in resistors, like PDTC series) Another possibility is to use some small NMOSFET, like BSS138, but then you must also add another resistor of 10..100k between gate and ground. You may then control the base/gate of a transistor with some PWM timer output.

View solution in original post

1 REPLY 1
gbm
Lead II

Check the schematic. The backlight is permanently connected to power supply via resistor R8, so there is no way to control it. You may modify the board by removing R8 from its position and soldering it in series with an NPN RET (bipolar transistor with build-in resistors, like PDTC series) Another possibility is to use some small NMOSFET, like BSS138, but then you must also add another resistor of 10..100k between gate and ground. You may then control the base/gate of a transistor with some PWM timer output.